Etiology

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Pathophysiology

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Clinical features

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Diagnostics

Light criteria

Tip

• Total protein normal level 6.0 to 8.3 g/dL (60 to 83 g/L)
• Albumin normal level 3.4 to 5.4 g/dL (34 to 54 g/L)
• LDH normal level 105 to 333 U/L

Satisfying any ONE criterium means it is exudative:

• Pleural Total Protein/Serum Total Protein ratio > 0.5
• Pleural lactate dehydrogenase/Serum lactate dehydrogenase ratio > 0.6
• Pleural lactate dehydrogenase level > 2/3 upper limit of the laboratory’s reference range of serum lactate dehydrogenase.

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Treatment

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Subtypes

Pleural empyema

• Accumulation of pus in the pleural cavity
• Exudative effusion (bacterial colonization)
  • Differ from uncomplicated parapneumonic effusion, which is just exudative effusion (without direct bacterial invasion)